K58.9 — Irritable bowel syndrome, unspecified
Is K58.9 billable?
Yes, but K58.9 is an unspecified code. K58.9 is a valid, billable ICD-10-CM code for encounters from October 1, 2026 through September 30, 2027. However, K58.9 is an unspecified or catch-all code. Payers apply additional scrutiny to unspecified codes and many deny them when the medical record supports a more specific option, so check the documentation before selecting K58.9 — the more specific alternatives are listed below.
K58.9 at a glance
| Code | K58.9 |
|---|---|
| Description | Irritable bowel syndrome, unspecified |
| Billable | Yes |
| Code set | ICD-10-CM FY2027 |
| Valid for encounters | October 1, 2026 – September 30, 2027 |
Which MS-DRGs does K58.9 group to?
K58.9 sits in MDC 06 and helps define the logic of 2 MS-DRGs (version 44, FY2027). Which one a stay actually groups to also depends on procedures and secondary diagnoses.
- 391Esophagitis, Gastroenteritis and Miscellaneous Digestive Disorders with MCCmedical
- 392Esophagitis, Gastroenteritis and Miscellaneous Digestive Disorders without MCCmedical
How is K58.9 listed in the Alphabetic Index?
These are the routes through the Alphabetic Index that lead to K58.9. They show the wording a clinician may have documented, which often differs from the Tabular description.
- Colic › mucous (bilious) (infantile) (intestinal) (recurrent) (spasmodic)
- Colitis › spastic (acute) (catarrhal) (chronic) (noninfective) (hemorrhagic)
- Hypermobility, hypermotility › ileum
- Hypermobility, hypermotility › intestine
- Irritable, irritability › bowel
- Irritable, irritability › without diarrhea
- Irritable, irritability › colon
- Spasm, spastic, spasticity › colon (s)
- Spasm, spastic, spasticity › intestinal (s)
- Spasm, spastic, spasticity › sigmoid (s)
- Syndrome › irritable › bowel
Inclusion terms
Alternative wording in documentation that is classified to K58.9.
- Irritable bowel syndrome NOS
Excludes2 — not included here — inherited from Chapter 11
The conditions below are not part of K58.9, but a patient may have both at the same time. When documentation supports it, K58.9 and the excluded code may both be reported.
- certain conditions originating in the perinatal period (P04-P96)
- certain infectious and parasitic diseases (A00-B99)
- complications of pregnancy, childbirth and the puerperium (O00-O9A)
- congenital malformations, deformations and chromosomal abnormalities (Q00-Q99)
- endocrine, nutritional and metabolic diseases (E00-E88)
- injury, poisoning and certain other consequences of external causes (S00-T88)
- neoplasms (C00-D49)
- symptoms, signs and abnormal clinical and laboratory findings, not elsewhere classified (R00-R94)
How long has K58.9 existed?
K58.9 has been in ICD-10-CM since at least FY2016, the earliest fiscal year on record here.
- FY2025Irritable bowel syndrome without diarrheaIrritable bowel syndrome, unspecified
Derived from the official order files for FY2016–FY2026. FY2017 and FY2020 publish no order file, so those years are not covered.